Chalk up another overly generous contract deal for the Long Island Rail Road unions — at the public’s expense.

The MTA and five holdout LIRR unions reached a deal Monday night, ending a crippling three-day strike and avoiding more turmoil, just as the region gets set for Memorial Weekend.

More good news: Gov. Kathy Hochul claims the deal doesn’t “compromise affordability for Long Islanders” or “require any additional fare increases or tax increases.”

Cross your fingers she’s right.

The agreement was likely the best the public can hope for — given the union’s ability to strangle the region with a strike, New York pols’ heavy pro-labor tilt and that it’s an election year.

(Even Hochul’s GOP rival, Nassau County Executive Bruce Blakeman, shamefully urged her to cave to the unions.)

But the original hope was for the five unions to accept the same raises — totaling 9.5% over three years — all the other unions accepted.

Instead, they demanded an outrageous 6% raise for a fourth year, then lowered the ask to a still-outrageous 5% and, though details are not fully available, reportedly wound up with a 4.5% boost, with just minor give-backs in exchange.

That higher-than-inflation raise, by the way, is on top of salaries that already make them among the highest-paid rail workers in the nation.

And on top of obscene six-digit yearly overtime pay.

And on top of bizarre work-rules that let them collect up to three days’ pay for a single day’s work.

Plus, their deal will set a pattern for the powerful Transport Workers Union.

New Yorkers should hope this is the last time a measly 3,500 greedy union workers, serving 300,000 daily riders, are allowed to hold an entire region hostage by threatening a strike.

Unfortunately, though, the blackmail will continue until Congress fixes the federal Railway Labor Act, which, unlike New York’s Taylor Law, lets LIRR workers take such job actions.

New Yorkers who want to end such thuggery need to press their representatives — Hochul, Sen. Chuck Schumer, Rep. Hakeem Jeffries, local congressmen — to fix the Railway Labor Act.

The Taylor Law, which outlaws strikes for most public-sector workers in New York, is there for a reason: Public services — like transportation — are simply too essential to allow them to be held at the mercy of self-interested unions.

Without a federal fix, it’s only a matter of time before the region finds itself facing the same extortion as it did this week.